1. Field of the Invention
The present invention relates to a magnetic lock, and more particularly to a magnetic swing door lock having a pair of bolts adapted to be securely mounted on a doorframe and a metal block movably mounted on a door and having two clamping blocks movably mounted on the metal block and each provided with a retaining recess defined to correspond to one of the pair of bolts so that when the pair of bolts are received in the retaining recesses of the metal block, the abutment of the pair of bolts to side faces of the retaining recesses ensures the door will not be forced to open.
2. Description of Related Art
With reference to FIG. 7, a conventional magnetic lock is shown and has a first base (50) securely mounted on a doorframe (A) and a second base (60) securely mounted on a door (B).
With reference to FIG. 8, the first base (50) has a hollow frame (51) provided with a metal block (52) which is integrally formed inside the frame (51). An electrical magnet (53) is provided around the metal block (52) so that when electrical power is provided to the electrical magnet (53), a magnetic field is thus generated. Two holes (520) are defined in the metal block (52) to respectively allow the extension of two bolts (54). Each of the bolts (54) has a head (540) and the heads (540) protrude out of an outer face of the metal block (52).
The second base (60) has a second frame (61) and a second metal block (62) is movably received in the second frame (61). The second metal block (62) has two retaining recesses (620) defined to correspond to the two heads (540) in the first base (50).
With reference to FIG. 9, an extension hole (621) is defined through the second metal block (62) such that a retainer (63) is able to extend through the extension hole (621) to secure the second metal block (62) on the second base (60). A spring (64) is sandwiched between a bottom face defining the extension hole (621) and a head of the retainer so that the second metal block (62) is movable relative to the second base (60).
When the conventional magnetic lock is assembled, the two heads (540) correspond to the two retaining recesses (620).
With reference to FIGS. 10 and 11, when an electrical current is provided to the electrical magnet (53), the magnetic field attracts the second metal block (62) to move toward the metal block (52), which compresses the springs (64) and thus stores a recovery force for the second metal block (62). After the second metal block (62) moves upward to the metal block (52), the two heads (540) are respectively received in the retaining recesses (620). Referring to FIG. 7 and FIG. 8, the bolt (54) in the first frame (51) and away from the door frame (A) is designated with another reference (C) and the bolt (54) in the first frame (51) and close to the door frame (A) is designated with another reference (D).
Therefore, when the magnetic lock of this kind is activated and the heads (540) are respectively received in the retaining recesses (620), pushing the door (B) violently by a person who is not aware of the fact that the door (B) is actually locked by the magnetic lock will do serious damage to the bolt (D). That is, in order to successfully receive therein the heads (540), the dimension of the retaining recesses (620) is larger than that of the bolts (54). As a result, even after the heads (540) are received in the retaining recesses (620), there is still room left in the retaining recesses (620), which allows a person unaware of that the door (B) is actually locked to push the door (B). Because of the room left in the retaining recess (620), pushing the door (B) while the door (B) is locked will especially and seriously damage the bolt (D) instead of the bolt (C). Furthermore, with reference to FIG. 12, after the heads (540) are to be received in the retaining recesses (620), only one bolt (D) is securely received in the corresponding retaining recess (620) such that pushing the door (B) will cause the second metal block (62) to tilt and make the lock failed. Therefore, even when the door (B) is locked, an unauthorized personnel may still easily open the door (B). Besides, because there is only a single engagement between the retaining recess (620) and one of the heads (540), the engagement force is not enough to withstand the force trying to open the door and will thus cause rotation. Therefore, after a period of time repeatedly pushing the locked door (B) will definitely wear the side faces of the retaining recesses (620). As a consequence of pushing the locked door (B) violently, the conventional magnetic lock becomes useless and replacement is necessary. Further, a hexagonal countersunk hole normally is defined in each of the heads (540). However, due to the existence of the hexagonal countersunk hole in the heads (540), the strength of the bolt (54) is weak and thus is not rigid enough to withstand a long term use.
To overcome the shortcomings, the present invention tends to provide an improved magnetic lock to mitigate and obviate the aforementioned problems.
The primary objective of the present invention is to provide an improved magnetic lock having a pair of strengthened solid bolts and a pair of clamping blocks movable relative to the pair of bolts such that the magnetic lock is able to better withstand an external force exerted on the door trying to open the door when the door is locked to the doorframe.
In order to accomplish the foregoing objective, the magnetic lock of the present invention is provided with a pair of bolts adapted to be mounted on a doorframe and a metal block movably mounted on a door and having two clamping blocks movably mounted on the metal block and each clamping block provided with a retaining recess defined to correspond to one of the pair of bolts so that when the pair of bolts are received in the retaining recesses of the metal block, the abutment of the pair of bolts to side faces of the clamping blocks in the same time can hold metal block from tilting and ensures the door will not be forced to open.